This invention generally relates to effluent samplers and more particularly, to an effluent sampler of improved efficiency, accuracy and structural design.
Effluent samplers are used to monitor the composition of effluent being discharged from a factory or mill. A sampler selectaby removes a sample of effluent from an effluent stream and retains samples for subsequent chemical analysis. By analyzing these samples, it can be determined whether manufacturing processes within the facility are working properly or whether discharges of excessive wastes are occurring.
Representative effluent samplers are disclosed in U.S. Pat. Nos. 2,270,511 to Crain and 2,958,222 to Morgan. In Crain, the sampler rests atop the effluent conduit adjacent to an opening for access to an effluent stream. An arm having a sample cup is pivotally connected to a motor drive. At the bottom of the cut is a valve to permit entry of effluent materials. In operation, the motor drive lowers the arm and cup from above the conduit through the opening and into the stream. Fluid collects through the valve in the bottom of the cup, and the arm and the cup are then raised from the stream and the sample is deposited in a storage container.
Morgan discloses a sampler mounted above the effluent stream. The sample is gathered by a pivoting arm with an opening at one end for retention of a sample. The arm pivots into the stream flow and then rises to pour the sample into a receptacle. To control admission of effluent into the arm, the opening is selectively opened or closed by a gate.
Other samplers are shown in U.S. Pat. Nos. 3,563,096 to Kinkelaar, 3,267,737 to Biebighauser, and 2,388,801 to Roetman. Kinkelaar shows a sampler that mounts above the effluent conduit. It samples the effluent with a sample container suspended from a motor unit. The container is lowered into the effluent stream and the sample is collected. The container is then raised and inverted to discharge the sample into a receptacle.
Biebighauser discloses a sampler that is affixed to a surface within the effluent conduit. It samples the effluent stram with a collecting cup mounted on a reciprocating arm. The reciprocating arm extends into the effluent stream to collect the sample and twists as it retracts to pour the sample into a receptacle.
In Roetman, the sampler is mounted above the effluent stream within a collection flume. It includes a catch basin to which a dipper is pivotally connected. The dipper dips downward into the stram to obtain a sample and then pivots uward to pour the sample into the catch basin.
The primary drawback of these samplers and others in the prior art is the inconvenience of use. Effluent streams generally flow in a conduit through a facility. Effluent samplers that must be mounted within the conduit are largely inaccessible for recovering their samples. Those that are mounted above the conduit, on the other hand, often present an obstruction in the facility.
Another drawback of the prior art is its failure to furnish a representative sample of the discharged effluent. The samples that are collected in the receptacle contain particulate matter and liquids of varying densities that filter into different layers within the container. The sample recovered from the container may not reflect a true mix of the effluent actually discharged and will likely include less particulate matter and lighter fluids.
The prior art also lacks means for easily cleaning an effluent sampler. If not removed from the sampler, particulate matter can deposit within an arm or dipper and eventually block flow of effluent to the collection point or may later dissolve to contaminate future samples.